The present disclosure relates to a printing device. More particularly, it relates to a printing device that discharges a printed label to the outside.
The present disclosure relates to a printing device. More particularly, it relates to a printing device that discharges a printed label to the outside.
Conventionally, printing devices having a tape cassette detachably loaded therein to produce tape-like labels are known. The tape cassette used in the printing device includes therein, for example, a transparent film tape on which letters and the like are printed, and a double sided adhesive tape bonded to the backside of the transparent film tape after the printing. A tape transfer roller is provided near a tape discharge port of the tape cassette for discharging the transparent film tape after the printing and the double sided adhesive tape bonded together to the outside.
This printing device includes a tape drive cam fitted in a shaft hole provided in the tape transfer roller, and a press roller rotatably attached to a position opposite the tape drive cam. When printing, the transparent film tape after the printing and the double sided adhesive tape are held and pressed together between the tape transfer roller and the press roller, and discharged to the outside.
The tape drive cam is generally composed by a tape drive cam gear, a cam member, and a tape drive cam support shaft made of metal and provided at the center of the tape drive cam. The tape drive cam gear and the cam member are formed integrally with each other and provided on an outer circumference of the tape drive cam support shaft. The lower part of the tape drive cam support shaft is fixed by a metal frame.
When the tape cassette is loaded in the printing device, the tape drive cam fits in the shaft hole in the tape transfer roller, whereby the tape transfer roller is appropriately positioned. Driving power from the motor is transmitted to the tape transfer roller of the tape cassette via the tape drive cam gear and the cam member. Thus the tape transfer roller rotates.
Generally, a press roller gear is provided under the press roller. The press roller gear is biased toward the tape drive cam gear to engage with the same. The press roller presses the tape transfer roller through the transparent film tape and the double sided adhesive tape. During printing, driving power from the motor is transmitted to the press roller gear via the tape drive cam gear. This rotates the press roller gear and the press roller. The tape transfer roller also rotates. Thus the printed tape and the double sided adhesive tape are held and pressed together between the tape transfer roller and the press roller and discharged to the outside.
In this conventional printing device described above, as the press roller presses the tape transfer roller provided in the tape cassette, a large pressure is applied to the tape drive cam that supports the tape transfer roller. The tape drive cam support shaft, which is the center axis of the tape drive cam, is therefore subjected to a large pressure. The press roller gear is biased toward the tape drive cam gear to engage with the same. Therefore, the pressure from the press roller gear is applied to the tape drive cam support shaft via the tape drive cam gear. That is, the pressure from the press roller and the pressure from the press roller gear are both applied to the tape drive cam support shaft. Any pressure applied to the tape drive cam support shaft also causes a force to be applied to the frame that anchors the tape drive cam support shaft. Therefore, the tape drive cam support shaft and the frame that anchors the tape drive cam support shaft are required to have high strength. Accordingly, metal having high strength is used for the tape drive cam support shaft and the frame.